Residential water distillers have gained in popularity as a result of an increased concern about drinking water quality. By far, the most common type of residential distiller is the counter-top design generally shown in U.S. Pat. No. 4,052,267 to McFee. Counter-top distillers, while inexpensive to purchase, consume large amounts of energy which is exhausted into the atmosphere. In the case of air conditioned homes, not only is the energy exhausted to the atmosphere wasted, but additional energy is also needed to cool the house. In order to minimize the energy dissipated into the room, there have been efforts to develop a water distiller which is cooled by tap water, which can then be poured down a drain. An example of such a water cooled distiller is shown in U.S. Pat. Nos. 4,342,625 to Dennison and 4,861,435 to Sweet. Water distillers of both water and air cooled designs are relatively inefficient, since large amounts of waste heat are a necessary by-product of the distilling operation.
There have been efforts over the years to utilize waste heat generated from water distilling systems. U.S. Pat. No. 4,601,789 to Bjorklund discloses a combined water distiller/hot water heater, where the latent heat of evaporation released during the condensation process is used to heat hot water. U.S. Pat. No. 4,549,936 to Erickson discloses a rather complex distillation system which is attached to a hot water heater and uses a pair of pumps to generate a sub-atmospheric region to cause the heated hot water to boil in the distiller without supplemental heating. U.S. Pat. No. 4,687,550 to Wong discloses a multichamber water distiller which generates atmospheric pressure waste water which is dumped down the sink drain or used as hot water for washing purposes. U.S. Pat. No. 797,255 to Beers illustrates a water distilling apparatus provided with a condensing coil for transferring the heat rejected during distillation to a hot water tank.